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Numerical simulation of hydrodynamic characteristics and bedload transport in cross sections of two gravel-bed rivers based on one-dimensional lateral distribution method

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International Journal of Sediment Research 2020年第2期35卷 203-216页

作者： Chien Pham Van vivien Chua Department of River Engineering and Disaster Management Faculty of Hydrology and Water ResourcesThuyloi University Unite de Mod'elisation Mathematiques et Informatiquedes Systemesco Complexes (UMMISCO) JEAI WARMIRDSorbonne Universit'e Department of Civil and Environmental Engineering Faculty of EngineeringNational University of Singapore

Accurate evaluation and prediction of bedload transport are crucial in studies of fluvial hydrodynamic characteristics and river *** paper presents a one-dimensional numerical model based on the one-dimensional lateral distribution method(1 D-LDM) and six classic bedload transport formulae that can be used to simulate hydrodynamic characteristics and bedload transport discharge in cross *** gravel-bed rivers,*** Danube River located approximately 70 km downstream from Bratislava in Slovakia and the Tolten River in south of Chile are used as *** the 1 D-LDM,gravity,bed shear stress,turbulent diffusion,and secondary flow are included to allow for accurate predictions of flow velocity and consequently bed shear stress in the cross *** classic formulae were applied to evaluate the non-dimensional bedload transport rate,and the bedload transport discharge through a river cross section is obtained by integrating the bedload transport rate over the width of the cross *** results show that the root mean square error(RMSE) and mean absolute error(MAE) of velocity and water discharge were less than 8% of the observed magnitude,while the correlation coefficient between model predictions and observations was close to *** formulae proposed by Ashida and Michiue(1972),in which particle collision with the bed is taken into account,and by Camenen and Larson(2005),which allows for yielding a non-zero bedload transport rate even when the bed shear stress is smaller than the critical bed shear stress value,appeared to be more appropriate for predicting the observed bedload transport rate in the studied cross sections of two gravel-bed *** non-uniform sediment mixtures were considered,the bedload transport discharge through a cross-section could change considerably by up to 22.5% of the observed *** relations proposed by Ashida and Michiue(1972) and Egiazaroff(1965) for parameterizing the hiding factor yielded more

关键词： Bedload Gravel-bed river One-dimensional lateral distribution method Bedload transport discharge

Scenario-based verification in presence of variability using a synchronous approach

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Frontiers of Computer Science 2013年第5期7卷 650-672页

作者： Jean-vivien MILLO Frederic MALLET Anthony COADOU S RAMESH INRIA Sophia-Antipolis Aoste team (INRIA/I3S/CNRS/UNS) Sophia-Antipolis 06560 France University of Nice Sophia Antipolis Sophia-Antipolis 06900 France Global General Motors R&D India Science Lab GM Technical Center India Bangalore 560066 India

This paper presents a new model of scenarios, dedicated to the specification and verification of system be- haviours in the context of software product lines （SPL）. We draw our inspiration from some techniques that are mostly used in the hardware community, and we show how they could be applied to the verification of software components. We point out the benefits of synchronous languages and mod- els to bridge the gap between both worlds.

关键词： Esterel UML MARTE scenario verification,feature interaction variability

Targeting the premetastatic niche:epigenetic therapies in the spotlight

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Signal Transduction and Targeted Therapy 2020年第1期5卷 1871-1872页

作者： vivien Low John Blenis Ana P.Gomes Meyer Cancer Center Weill Cornell MedicineNew YorkNYUSA Department of Pharmacology Weill Cornell MedicineNew YorkNYUSA

The treatment of metastatic cancers remains a challenge in the clinic,with recurrences persisting at high rates even after surgical resection of primary *** the perseverance of circulating tumor cells after resection,this phenomenon is abetted by the formation of the premetastatic niche(PMN),a distant environment ripe for the colonization of new metastases,which is conditioned by factors and extracellular vesicles secreted by the primary *** their recent paper,Lu et *** how such PMNs in the lung can be disrupted by low-dose adjuvant epigenetic therapy,and propose a novel therapeutic avenue to supplement tumor resection.

关键词： metastatic epigenetic al

English Private Tutoring in Macao:Perceptions of Senior Secondary Three Students

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ECNU Review of Education 2019年第1期2卷 44-63页

作者： vivien Nga Man Chan The University of Hong Kong China

Purpose:This article examines how individual,school,and social factors shape the perceptions of students in Senior Secondary Three(SS3;in some schools called Form Six[F6])toward English private tutoring in ***/Approach/Methods:This is a comparative study of two F6 classes of an English-medium secondary school and four SS3 classes of a Chinese-medium secondary school in Macao,with a total number of 145 ***-methods approach(questionnaires and interviews)is employed in the ***:The respondents’participation in English tutoring is not very *** prefer to receive government-subsidized after-school tutoring taught by their schoolteachers more than feepaying English tutoring taught by tutors *** level of social competition and high tertiary enrollment rates contribute to this ***’needs and beliefs in English learning play key roles in determining their receipt of English ***/Value:Teachers may need better understanding of their students’needs so as to design suitable *** can consider more fully the types of tutoring that they provide for different kinds of *** government-subsidized after-school tutoring could be a plausible way to reduce educational inequality.

关键词： English Macao perceived needs private tutoring shadow education

FCA-based E-Government System Modeling and Prototyping System Implementation

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FCA-based E-Government System Modeling and Prototyping Syste...

作者： vivien Loua（卫恩）大连海事大学

学位级别：硕士

为了弄清不断变化的环境对政府的影响,本文剖析了有关政府和电子政务的基本理论、全球范围的政府转变观念和发展趋势以及几内亚政府改革进程回顾与展望。为理解这些定性因素以便对政府形成充分认识,我们需要对现有的工具和方法进行分析... 详细信息

为了弄清不断变化的环境对政府的影响,本文剖析了有关政府和电子政务的基本理论、全球范围的政府转变观念和发展趋势以及几内亚政府改革进程回顾与展望。为理解这些定性因素以便对政府形成充分认识,我们需要对现有的工具和方法进行分析研究。目前,信息系统建模和企业建模的工具和方法已有许多可以借鉴的成果,因此,在政府建模和参考案例尚不成熟的情况下,参照并选择企业建模方法和建模工具来构建适用于电子政务的政府建模是一种可行的方法。本文提出了政府建模的目的和范围,并对政府建模因素和政府模型进行了深入分析。将电子政务建模作为政府研究基础,有助于更好地理解复杂的政府管理和其运作模式,并可以为电子政务信息系统的设计和开发提供一个参考和设计基础。形式概念分析(Formal Concept Analysis, FCA)作为应用数学的一个分支,可以对那些有某种内在关联关系或共享共性特征的元素进行分类,并可以借助对其进行数学表达,发现其中的概念和概念间关系。要高度提炼和充分解耦业务实体模型(Business Entity Model)并解决传统业务模型中普遍存在的非均匀粒度抽象(Non-uniform granularity abstract)和主观因素干扰(Subjective factors interference)问题,本文探讨一种基于形式概念分析(FCA)系统分析和设计方法。借助FCA理论和方法,本文分别对业务实体分析与数据库设计、模块分析与功能设计、基于SOA的可重用服务组件与系统集成的作用等问题进行了分析和探讨。同时,对基于上述分析方法与设计模型的可操作步骤进行了充分解析。针对一个电子政务的实际核心业务系统,本文给出了一些用于克服各类风险的可选策略。借助FCA,本文分别进行了实体抽象、概念层次分析、概念格属性聚类以及数据库结构分析,进而最终得到业务实体模型。本文实现的一个实际电子政务原型系统证实,本文提出的基于FCA的电子政务建模方法在业务实体分析、数据库分析及数据库结构设计等过程中的是有效和可行的。

关键词：电子政务形式概念分析概念格哈斯图可重用服务系统建模

Adsorption of methane on biochar for emission reduction in oil and gas fields

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Biochar 2023年第1期5卷 290-301页

作者： vivien Yoonhee Ko Jinsheng Wang lan He David Ryan Xiaojie Zhang Christopher Lan Natural Resources Canada CanmetENERGY1 Haanel Dr.OttawaON K1A 1M1Canada FPInnovations 2665 East MallVancouverBC V6T 1Z4Canada Department of Chemical and Biological Engineering University of Ottawa161 Louis Pasteur StreetOttawaON K1N 6N5Canada

To contribute to the reduction of methane emissions,using low-cost biochar as adsorbents for capturing and storing methane in oil and gas fields is *** work presents results of methane adsorption on four biochars made from forestry wastes in comparison with the results of three commercial activated *** the adsorption capacity of the biochars is lower by over 50%than that of the activated carbons,thelow-cost and potential environmental benefits provide the incentive to the ***,it is shown that biochar can store more methane than vessels of compressed gas up to the pressure of 75 bar,suggesting the possibility of avoiding high-pressure gas compression and heavy vessels for cost savings in oil and gas *** thermodynamic and kinetic behaviors of the adsorption are studied and implications for the targeted application are discussed.

关键词： Biochar Adsorbent Methane emissions Greenhouse gas reduction Adsorption behavior

Thrombolysis of stroke mimics via telestroke

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Stroke & Vascular Neurology 2022年第3期7卷 267-270页

作者： vivien H Lee Ravyn Howell Randheer Yadav Sharon Heaton Karen L Wiles Sushil Lakhani Neurology The Ohio State University Wexner Medical CenterColumbusOhioUSA

Background The rate of intravenous tissue plasminogen activator(IVtPA)administered to stroke mimics(SM)occurs in 24%-44%of telestroke *** We reviewed 270 suspected acute ischaemic stroke(AIS)patients who were evaluated by telestroke and received IVtPA from 1 July 2016 to 30 September 2017 at our academic comprehensive stroke *** Among 270 AIS patients who received IVtPA via telestroke,64(23.7%)were diagnosed with *** with patients who had a stroke,the SM group was younger(mean age 56.4 vs 68.2,p<0.0001),more likely to be female(60.9%vs 45.6%,p=0.0324)and had longer door-to needle times(85.3 vs 69.9,p=0.0008).The most common SM diagnoses were migraine 26(40.6%),conversion disorder 12(18.8%),encephalopathy 7(10.9%)and unmasking(9.4%).Among the SM,migraine and conversion disorder were younger compared with the other subgroups(p<0.001).Functional exam elements were noted more frequently in conversion disorder(66.7%)and migraine(34.6%),but rare in other diagnoses(p=0.006).Among the SM,23(35.9%)had a history of a prior similar episodes,and 15(23.4%)had a history of more than 5 *** In our telestroke programme,23.7%of those administered thrombolysis had a final diagnosis of SM.

关键词： needle diagnosis younger

UAV-mounted Ground Penetrating Radar: an example for the stability analysis of a mountain rock debris slope

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Journal of Mountain Science 2023年第10期20卷 2804-2821页

作者： Riccardo SALVINI Luisa BELTRAMONE vivien DE LUCIA Andrea ERMINI Claudio VANNESCHI Caterina ZEI Daniele SILVESTRI Andrea RINDINELLA Department of Environment Earth and Physical Sciences and Centre of Geotechnologies CGTUniversity of SienaVia Vetri Vecchi 3452027San Giovanni Valdarno(Arezzo)Italy Direzione Urbanistica Settore Sistema Informativo e Pianificazione del TerritorioRegione ToscanaVia di Novoli 2650127 FlorenceItaly Department of Physics and Earth Science University of FerraraVia Giuseppe Saragat 144122FerraraItaly

This paper describes scientific research conducted to highlight the potential of an integrated GPR-UAV system in engineering-geological *** analysis focused on the stability of a natural scree slope in the Germanasca Valley,in the western Italian *** a consequence of its steep shape and the related geological hazard,the study used different remote sensed methodologies such as UAV photogrammetry and geophysics survey by a GPR-drone integrated ***,conventional in-situ surveys led to the collection of geological and geomorphological *** use of the UAV-mounted GPR allowed us to investigate the bedrock depth under the detrital slope deposit,using a non-invasive technique able to conduct surveys on inaccessible areas prone to hazardous conditions for *** collected evidence and the results of the analysis highlighted the stability of the slope with Factors of Safety,verified in static conditions(i.e.,natural static condition and static condition with snow cover),slightly above the stability limit value of *** the contrary,the dynamic loading conditions(i.e.,seismic action applied)showed a Factor of Safety below the stability limit *** UAV-mounted GPR represented an essential contribution to the surveys allowing the definition of the interface debris deposit-bedrock,which are useful to design the slope model and to evaluate the scree slope stability in different conditions.

关键词： GroundPenetrating Radar(GPR) Unmanned AerialVehicle e(UAV) GPR-drone integrated system Slope stability analysis Static and dynamic loading conditions

Sensors Applied in Healthcare Environments

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Journal of Computer and Communications 2016年第5期4卷 99-106页

作者： Wei vivien Shi Department of Engineering & Technology University of Wisconsin-Stout Menomonie USA

In this paper, the recent advances of sensors applied in healthcare environments are presented. Based on the function and operation of modern health and wellness measurement and monitoring and mHealth solutions, a variety of sensors are described with their features and applications. Further improvements and future trend are pointed out and discussed.

关键词： Healthcare Sensors mHealth Security